From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Solutions for oil leakage from the back of 20/25 HP and 40/50 HP gearboxes.
| Identifier | ExFiles\Box 6\4\ 04-page261 | |
| Date | 20th August 1930 | |
| COPY. X5310 DA.{Bernard Day - Chassis Design} BY3/G.20.8.30. c. Hs.{Lord Ernest Hives - Chair} ----- X.7310. X.5310. 20/25 HP. and 40/50 HP. GEAR BOXES. RE LEAKAGE OF OIL FROM THE BACK OF THE BOX. We notice on the 20 HP. scheme recently sent us that in order to obviate the leakage of oil past the returning screw on the third motion shaft you have drilled a hole in the cover to communicate between the interior of the box and the space enclosed by the pressing on the outside of the cover. We understand also that this is to be applied to the 40/50 HP. but it appears to us this scheme is useless as since oil leaks out past the acme return thread there must be a pressure of oil between the bearing and the gearbox greater than the returning force imposed by the acme thread. If this is so, to drill a hole from this space where pressure is exerted inside the box to the outside of the cover, will only allow the oil to flow out perfectly freely. We would suggest that it is reasonable to cut a returning groove down the face of the cover on the inside to communicate with a hole drilled below the bearing to permit the oil to drain back into the interior of the box, thus by passing the bearing by the groove. We attach a scheme of our proposal and would suggest in the first place that this is tried out. Frankly, I cannot understand why a thrower has been put outside of the box on the third motion shaft, which in conjunction with the pressing on the cover is supposed to collect the oil to return it to the box, as if the oil passes the screw thread there can be no hope of its return, and one feels that the right thing to do is to prevent it passing the screw thread, as we have always managed to do in the past, by giving adequate oil return to the interior of the box. BY.{R.W. Bailey - Chief Engineer} | ||